## p-channel MOSFET

The equations for the drain current of a p-channel MOSFET in cut-off, linear and saturation mode are:

Here *I*_{D} is the drain current, *V*_{DS} is the drain-source voltage, *V*_{GS} is the gate-source voltage, *V*_{T} is the threshold voltage, *L* is the length of the transistor, *W* is the width of the transistor, *C*_{ox} is the specific capacitance of the gate in F/m², and *μ*_{p} is the mobility.

MOSFET charateristics are typically drawn for serveral gate voltages.
In the figure below, the threshold voltage is -0.7 V and the gate voltages
are -2, -3, -4, -5 and -6 V.